Sometimes reality is better than fiction — and for Atletico Madrid players and fans, this soccer season has been a pure fairy tale.

On paper, Atletico shouldn’t have reached the UEFA Champions League Final on Saturday, let alone have a decent chance of winning the coveted soccer trophy. The Madrid team is one of the most heavily in debt in Spanish sports, which means, for one thing, that it lacks the financial firepower to buy high-profile international players such as Cristiano Ronaldo and Gareth Bale of Real Madrid, which it’ll meet in the final.

Last season, underdog Atletico pulled in 120 million euros ($163 million) in revenue, while Real had an impressive €519 million on the top line. When it comes to debt, Real’s debt-to-equity ratio sits at 1.73 — seen as acceptable in the world of Spanish football, according to a report by University of Barcelona academic Jose Maria Gay. It’s a different picture for Atletico, which is weighed down by debt that’s more than 16 times its net worth.

“Atletico has been a surprise this year, because they had to compete with a lower budget and less good players,” said Jaume Llopis, a soccer finance expert from the IESE business school in Barcelona. “But the financial situation for Atletico is extremely difficult. Even if they win the Champions League, it won’t be enough to recover from its economic situation.”

But where there’s a will, there’s a way. Everything fell into place — a motivational coach, hardworking players and dedicated fans — and now Atletico is closer to becoming the European champion than it’s been in four decades. It won La Liga, the Spanish regular-season championship, this year for the first time in 18 years, beating Real Madrid and Barcelona — each, on paper, its vast superior.

Jose Carmona, 32, and Raul Reyes, 51, both work at Lalos, a meat vendor in a food market in Madrid’s upscale Salamanca district. The area’s more or less the home of Real Madrid, whose stadium is not far away. Neither they nor the bulk of their colleagues at the market live in the area, which they say is just too expensive.

But Reyes is a Real Madrid fan, while Carmona supports Atletico. Motioning to the fish vedor, the fruit stand and other stalls around him, Carmona says the majority of the workers support Atletico. There’s lots of rivalry in the tiny space where the two men slice choice cuts of beef and Spanish hams, but they agree it’s been a spectacular and amazing year for Atletico and that the tiny underdog has earned its shot at being champion.

“It’s been 40 years since Atletico have made it to this point,” said Carmona, referring to the last time his team reached the final of Europe’s major club tournament, when it lost to Bayern Munich. “It’s our time.”

“Above all, it’s been Atletico’s coach,” said Reyes, referring to Argentine-born Diego Simeone, the team’s manager, also a former player. In a recent game he could be seen running along the sideline, leaping in the air for joy as his team scored. “He’s encouraged them and gotten the best out of them,” said Reyes.

For a football-mad city like Madrid, the matchup on Saturday is a bit of a dream come true. Spain often has a team in the Champions League final — but it’s rare for two Spanish sides to meet. And two from the same city, in whatever country? Forget it. It’s never happened before this year.

Barbara Kollmeyer/MarketWatch

As for who’ll win, Carmona says Atletico and Real Madrid have equal chances. But in a bar downstairs from the food market, a group of construction workers is unanimous in the belief that Real Madrid will steamroll Atletico and its fans’ Cinderella dreams.

Real Madrid is also the favorite according to betting website Paddy Power.

No matter who wins, the after-game celebrations will fill the streets of Madrid. But once the confetti is swept up, Atletico, even if victorious, will find itself no better off, believes Carmona.

“Atletico has a lot of debt. It could improve in some aspect economically — cut back on some debt — but they will have to sell players this year,” he says.

So much for riding the fairy tale. IESE’s Llopis estimates Atletico could make €180 million by selling its best players and pull in €50 million from UEFA, the European football organization, if it wins the Champions League final. Given that it’s more than €500 million in debt, the transfer revenue and prize money cannot fund a complete financial comeback.

“Even if the situation has improved now, the long-term situation is very difficult,” Llopis said.

Like most other Spanish clubs, the underdog Madrid team owes money to the government — around €80 million, to be exact. All together, the 42 clubs in the top two divisions of Spanish soccer hold €3.2 billion in debt. Of that, €700 million is owed to Spain’s Treasury. But, unlike many creditors, the Treasury is in no rush to claw back the money.

“The government doesn’t push the teams to pay back the debt. If the government makes them pay, the majority of the clubs would end in bankruptcy,and that would practically be the end of Spanish football,” Llopis said.

“Tomorrow, for the Champions League final, there are 6 million people without a job who will forget they don’t have a job. Football is very popular.”

The match is to be played in Lisbon on Saturday at 7:45 p.m. local time, or 2:45 p.m. in the U.S.’s Eastern time zone.

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